/**
 * SpeakVlog 英语学习主题样式
 * 模仿 speakvlog.com 网站设计
 * 深色主题，现代简约风格
 */

/* ==================== CSS 变量 ==================== */
:root {
    /* 主色调 - 浅色主题 */
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #f1f5f9;
    --bg-card: #ffffff;
    --bg-hover: #f1f5f9;

    /* 强调色 */
    --accent-primary: #6366f1;
    --accent-secondary: #8b5cf6;
    --accent-gradient: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);

    /* 文字颜色 */
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-tertiary: #94a3b8;
    --text-muted: #cbd5e1;
    
    /* 状态颜色 */
    --success: #22c55e;
    --warning: #f59e0b;
    --error: #ef4444;
    --info: #3b82f6;
    
    /* 边框 */
    --border-color: #e2e8f0;
    --border-light: #cbd5e1;
    
    /* 间距 */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-2xl: 48px;
    
    /* 圆角 */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-full: 9999px;
    
    /* 阴影 */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.5);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.6);
    
    /* 过渡 */
    --transition-fast: 150ms ease;
    --transition-base: 200ms ease;
    --transition-slow: 300ms ease;
    
    /* 字体 */
    --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    --font-mono: "SF Mono", Monaco, "Cascadia Code", "Roboto Mono", monospace;
}

/* ==================== 全局重置 ==================== */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-sans);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

a {
    color: inherit;
    text-decoration: none;
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

/* ==================== 页面包装器 ==================== */
.speakvlog-wrapper {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* ==================== 顶部导航 ==================== */
.speakvlog-header {
    position: sticky;
    top: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 var(--spacing-xl);
    height: 64px;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-color);
}

.header-left {
    display: flex;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 20px;
    font-weight: 700;
    color: var(--text-primary);
}

.logo-icon {
    font-size: 24px;
}

.logo-text {
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.header-nav {
    display: flex;
    align-items: center;
    gap: var(--spacing-xl);
}

.nav-link {
    position: relative;
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
    transition: color var(--transition-fast);
    padding: var(--spacing-sm) 0;
}

.nav-link:hover,
.nav-link.active {
    color: var(--text-primary);
}

.nav-link.active::after '';
    position: {
    content: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--accent-gradient);
    border-radius: var(--radius-full);
}

.header-right {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.search-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    transition: all var(--transition-fast);
    cursor: pointer;
}

.search-toggle:hover {
    background: var(--bg-hover);
    color: var(--text-primary);
}

.user-avatar {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-full);
    overflow: hidden;
    border: 2px solid var(--border-color);
    transition: border-color var(--transition-fast);
}

.user-avatar:hover {
    border-color: var(--accent-primary);
}

.user-avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.login-btn {
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--accent-gradient);
    border-radius: var(--radius-md);
    font-size: 14px;
    font-weight: 600;
    color: white;
    transition: opacity var(--transition-fast);
}

.login-btn:hover {
    opacity: 0.9;
}

/* ==================== 主容器 ==================== */
.speakvlog-container {
    display: flex;
    flex: 1;
    max-width: 1600px;
    margin: 0 auto;
    width: 100%;
    padding: var(--spacing-xl);
    gap: var(--spacing-xl);
}

/* ==================== 侧边栏 ==================== */
.speakvlog-sidebar {
    width: 300px;
    flex-shrink: 0;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
    position: sticky;
    top: 80px;
    height: fit-content;
    max-height: calc(100vh - 100px);
    overflow-y: auto;
    scrollbar-width: none; /* Firefox */
    -ms-overflow-style: none; /* IE 10+ */
}

.speakvlog-sidebar::-webkit-scrollbar {
    display: none; /* Chrome, Safari, Opera */
}

/* 用户学习卡片 */
.user-study-card {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    border: 1px solid var(--border-color);
}

.user-info {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.user-avatar-large {
    width: 64px;
    height: 64px;
    border-radius: var(--radius-full);
    overflow: hidden;
    border: 3px solid var(--accent-primary);
}

.user-avatar-large img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.avatar-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-tertiary);
    font-size: 24px;
    color: var(--text-tertiary);
}

.user-name {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
}

.study-stats {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.stat-box {
    background: var(--bg-tertiary);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    text-align: center;
}

.stat-box.primary {
    background: var(--accent-gradient);
}

.stat-value {
    font-size: 28px;
    font-weight: 700;
    color: var(--text-primary);
    line-height: 1.2;
}

.stat-label {
    font-size: 12px;
    color: var(--text-secondary);
    margin-top: var(--spacing-xs);
}

.stat-box.primary .stat-label {
    color: rgba(255, 255, 255, 0.8);
}

.stat-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-sm);
}

.stat-grid .stat-box {
    padding: var(--spacing-sm);
}

.stat-grid .stat-value {
    font-size: 20px;
}

.stat-grid .stat-label {
    font-size: 11px;
}

/* 学习日历 */
.study-calendar {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    border: 1px solid var(--border-color);
}

.study-calendar h3 {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
}

.calendar-weekdays {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: 4px;
    margin-bottom: var(--spacing-sm);
}

.calendar-weekdays span {
    text-align: center;
    font-size: 11px;
    font-weight: 600;
    color: var(--text-tertiary);
    padding: var(--spacing-xs);
}

.calendar-days {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: 4px;
}

.calendar-day {
    aspect-ratio: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    color: var(--text-secondary);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.calendar-day:not(.empty):hover {
    background: var(--bg-hover);
    color: var(--text-primary);
}

.calendar-day.today {
    background: var(--accent-primary);
    color: white;
    font-weight: 600;
}

.calendar-day.studied {
    position: relative;
    color: var(--success);
}

.calendar-day.studied::after {
    content: '';
    position: absolute;
    bottom: 2px;
    left: 50%;
    transform: translateX(-50%);
    width: 4px;
    height: 4px;
    background: var(--success);
    border-radius: var(--radius-full);
}

/* 学习强度热力图样式 */
.calendar-day.studied-level-1 {
    background: #bbf7d0;
    color: #166534;
}

.calendar-day.studied-level-2 {
    background: #4ade80;
    color: #fff;
}

.calendar-day.studied-level-3 {
    background: #22c55e;
    color: #fff;
}

.calendar-day.studied-level-4 {
    background: #15803d;
    color: #fff;
}

.calendar-day.studied-level-1.today,
.calendar-day.studied-level-2.today,
.calendar-day.studied-level-3.today,
.calendar-day.studied-level-4.today {
    background: var(--accent-primary);
    color: #fff;
}

.calendar-day.empty {
    cursor: default;
}

/* 最近学习 */
.recent-learning {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    border: 1px solid var(--border-color);
}

.recent-learning h3 {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
}

.recent-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.recent-item {
    display: flex;
    gap: var(--spacing-md);
    padding: var(--spacing-sm);
    border-radius: var(--radius-md);
    transition: background var(--transition-fast);
}

.recent-item:hover {
    background: var(--bg-hover);
}

.recent-thumb {
    width: 60px;
    height: 40px;
    border-radius: var(--radius-sm);
    overflow: hidden;
    flex-shrink: 0;
}

.recent-thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.recent-info {
    flex: 1;
    min-width: 0;
}

.recent-title {
    font-size: 13px;
    font-weight: 500;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    margin-bottom: 4px;
}

.recent-meta {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 11px;
    color: var(--text-tertiary);
}

.progress-bar-mini {
    width: 60px;
    height: 3px;
    background: var(--bg-tertiary);
    border-radius: var(--radius-full);
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: var(--accent-primary);
    border-radius: var(--radius-full);
    transition: width var(--transition-slow);
}

/* ==================== 主内容区 ==================== */
.speakvlog-main {
    flex: 1;
    min-width: 0;
}

/* 页面标题 */
.page-header {
    margin-bottom: var(--spacing-xl);
}

.page-title h1 {
    font-size: 32px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.page-title p {
    font-size: 14px;
    color: var(--text-secondary);
}

/* 筛选导航 */
.filter-nav {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
    flex-wrap: wrap;
}

.filter-btn {
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 13px;
    font-weight: 500;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

.filter-btn:hover {
    background: var(--bg-hover);
    color: var(--text-primary);
    border-color: var(--border-light);
}

.filter-btn.active {
    background: var(--accent-primary);
    border-color: var(--accent-primary);
    color: white;
}

.filter-actions {
    margin-left: auto;
}

.search-input {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-tertiary);
    transition: all var(--transition-fast);
}

.search-input:focus-within {
    border-color: var(--accent-primary);
    background: var(--bg-tertiary);
}

.search-input input {
    background: none;
    border: none;
    outline: none;
    font-size: 13px;
    color: var(--text-primary);
    width: 200px;
}

.search-input input::placeholder {
    color: var(--text-tertiary);
}

/* 课程网格 */
.course-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
}

/* 课程卡片 */
.course-card {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    overflow: hidden;
    border: 1px solid var(--border-color);
    transition: all var(--transition-base);
}

.course-card:hover {
    transform: translateY(-4px);
    border-color: var(--border-light);
    box-shadow: var(--shadow-lg);
}

.course-card-link {
    display: block;
}

.course-thumbnail {
    position: relative;
    aspect-ratio: 16 / 9;
    overflow: hidden;
    background: var(--bg-tertiary);
}

.course-thumbnail img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

.course-card:hover .course-thumbnail img {
    transform: scale(1.05);
}

.course-overlay {
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.4);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity var(--transition-base);
}

.course-card:hover .course-overlay {
    opacity: 1;
}

.play-button {
    width: 56px;
    height: 56px;
    background: rgba(255, 255, 255, 0.95);
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--accent-primary);
    transform: scale(0.8);
    transition: transform var(--transition-base);
}

.course-card:hover .play-button {
    transform: scale(1);
}

.play-button svg {
    margin-left: 3px;
}

.course-duration {
    position: absolute;
    bottom: var(--spacing-sm);
    right: var(--spacing-sm);
    padding: 2px 8px;
    background: rgba(0, 0, 0, 0.75);
    border-radius: var(--radius-sm);
    font-size: 12px;
    font-weight: 500;
    color: white;
}

.course-progress-bar {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: rgba(0, 0, 0, 0.5);
}

.course-progress-fill {
    height: 100%;
    background: var(--accent-primary);
    transition: width var(--transition-slow);
}

.course-completed-badge {
    position: absolute;
    top: var(--spacing-sm);
    right: var(--spacing-sm);
    width: 28px;
    height: 28px;
    background: var(--success);
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
}

.course-body {
    padding: var(--spacing-md);
}

.course-meta-top {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
}

.course-category {
    font-size: 12px;
    color: var(--accent-primary);
    font-weight: 500;
}

.course-level {
    font-size: 11px;
    padding: 2px 8px;
    border-radius: var(--radius-sm);
    font-weight: 500;
}

.course-level.初级 {
    background: rgba(34, 197, 94, 0.15);
    color: var(--success);
}

.course-level.中级 {
    background: rgba(245, 158, 11, 0.15);
    color: var(--warning);
}

.course-level.高级 {
    background: rgba(239, 68, 68, 0.15);
    color: var(--error);
}

.course-title {
    font-size: 15px;
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1.4;
    margin-bottom: var(--spacing-sm);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    min-height: 42px;
}

.course-meta-bottom {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.course-lessons {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 12px;
    color: var(--text-tertiary);
}

.course-tags {
    display: flex;
    gap: var(--spacing-xs);
}

.course-tags .tag {
    font-size: 10px;
    padding: 2px 6px;
    background: var(--bg-tertiary);
    border-radius: var(--radius-sm);
    color: var(--text-tertiary);
}

/* 加载更多 */
.load-more {
    display: flex;
    justify-content: center;
    margin-top: var(--spacing-2xl);
}

.load-more-btn {
    padding: var(--spacing-md) var(--spacing-2xl);
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

.load-more-btn:hover {
    background: var(--bg-hover);
    border-color: var(--accent-primary);
    color: var(--text-primary);
}

/* ==================== 响应式设计 ==================== */
/* 平板设备 (768px - 1024px) */
@media (max-width: 1200px) {
    .speakvlog-container {
        flex-direction: column;
    }

    .speakvlog-sidebar {
        width: 100%;
        flex-direction: row;
        flex-wrap: wrap;
        position: static;
        max-height: none;
    }

    .user-study-card,
    .study-calendar,
    .recent-learning {
        flex: 1;
        min-width: 280px;
    }
}

@media (max-width: 1024px) {
    .course-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* 移动端设备 (< 768px) */
@media (max-width: 768px) {
    .speakvlog-header {
        padding: 0 var(--spacing-md);
    }

    .header-nav {
        display: none;
    }

    .speakvlog-container {
        padding: var(--spacing-md);
        flex-direction: column;
    }

    .speakvlog-sidebar {
        display: none;
    }

    .course-grid {
        grid-template-columns: 1fr;
    }

    .filter-nav {
        flex-direction: column;
        align-items: stretch;
    }

    .filter-actions {
        margin-left: 0;
        margin-top: var(--spacing-md);
    }

    .search-input {
        width: 100%;
    }

    .search-input input {
        width: 100%;
    }

    .page-title h1 {
        font-size: 24px;
    }

    .course-title {
        font-size: 14px;
    }

    .course-tags {
        display: none;
    }
}

/* 小屏幕手机 (< 480px) */
@media (max-width: 480px) {
    .speakvlog-header {
        height: 56px;
    }

    .logo-text {
        font-size: 14px;
    }

    .page-title h1 {
        font-size: 20px;
    }

    .page-title p {
        font-size: 13px;
    }

    .course-body {
        padding: 10px;
    }

    .course-title {
        font-size: 13px;
    }
}

/* ==================== 滚动条样式 ==================== */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--border-light);
    border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-tertiary);
}